Objective To investigate the role of interleukin-4 (IL-4) and interleukin-5 (IL-5) in the pathogenesis of steroid-resistant (SR) asthma.Methods Fifteen patients with SR asthma and 15 patients with steroid-sensitive (SS) asthma were selected based on their clinical responses to prednisone therapy. The peripheral blood mononuclear cells (PBMCs) were obtained and incubated with phytohemagglutinin (PHA) in vitro for 48 h in the presence or absence of dexamethasone (10-7 mol/L). Expressions of IL-4 and IL-5 mRNA in PBMCs were determined by reverse transcription-polymerase chain reaction (RT-PCR), and mRNA positive PBMCs for IL-4 and IL-5 were measured with in situ hybridization using digoxin-labeled cDNA probes.Results In the absence of dexamethasone, there was no significant difference in the expressions of IL-4 and IL-5 mRNA between SR and SS asthmatics, and the numbers of mRNA positive cells for IL-4 and IL-5 were also similar between these two groups, however, in the presence of dexamethasone (10-7 mol/L), expressions of IL-4 mRNA (P<0.01) and IL-5 mRNA (P<0.05) were significantly inhibited in SS asthmatics, but not in SR asthmatics (P>0.05). The numbers of IL-4 and IL-5 mRNA positive cells decreased from 5.50±1.60 to 2.27±0.98 (P<0.01) and from 5.03±1.29 to 1.67±0.70 (P<0.01), respectively in SS asthmatics, but in the patients with SR asthma, there was no significant change in the number of cells expressing mRNA for IL-4 or IL-5.Conclusion The gene expression of IL-4 and IL-5 in SR asthma was not inhibited by dexamethasone at the concentration of 10-7 mol/L. It is suggested that the relative unresponsiveness of T cells to glucocorticoids and persistent production of cytokines may be one of the mechanisms of steroid resistance in asthma.

Fascioliasis, a food-borne trematode zoonosis, is a disease primarily in cattle and sheep and occasionally in humans. Water dropwort (Oenanthe javanica), an aquatic perennial herb, is a common second intermediate host of Fasciola, and the fresh stems and leaves are widely used as a seasoning in the Korean diet. However, no information regarding Fasciola species contamination in water dropwort is available. Here, we collected 500 samples of water dropwort in 3 areas in Korea during February and March 2015, and the water dropwort contamination of Fasciola species was monitored by DNA sequencing analysis of the Fasciola hepatica and Fasciola gigantica specific mitochondrial cytochrome c oxidase subunit 1 (cox1) and nuclear ribosomal internal transcribed spacer 2 (ITS-2). Among the 500 samples assessed, the presence of F. hepatica cox1 and 1TS-2 markers were detected in 2 samples, and F. hepatica contamination was confirmed by sequencing analysis. The nucleotide sequences of cox1 PCR products from the 2 F. hepatica-contaminated samples were 96.5% identical to the F. hepatica cox1 sequences in GenBank, whereas F. gigantica cox1 sequences were 46.8% similar with the sequence detected from the cox1 positive samples. However, F. gigantica cox1 and ITS-2 markers were not detected by PCR in the 500 samples of water dropwort. Collectively, in this survey of the water dropwort contamination with Fasciola species, very low prevalence of F. hepatica contamination was detected in the samples.
Animals ; Base Sequence ; Cluster Analysis ; DNA, Helminth/chemistry/genetics ; DNA, Ribosomal Spacer/chemistry/*genetics ; Electron Transport Complex IV/*genetics ; Fasciola hepatica/*genetics/*isolation & purification ; Korea ; Molecular Sequence Data ; Oenanthe/*parasitology ; Phylogeny ; Sequence Analysis, DNA ; Sequence Homology, Nucleic Acid